A radio frequency device is an important component of the magnet resonance imaging equipment. It excites polarized nucleuses (such as 1H, 19F) in an object using radio frequency pulses transmitted by different radio frequency pulse sequences, so as to generate a plurality of magnetic resonance (MR) signals, and receive the MR signals.
Classified by functions, the radio frequency device includes radio frequency receiver and radio frequency transmitter. The radio frequency receiver is generally composed of a plurality of circuit units, such as receiving coil, preamplifier, local oscillator, mixer, filter, A/D converter (analog to digital converter), modem, and coupler, etc; the radio frequency transmitter is generally composed of a plurality of circuit units, such as D/A converter (digital to analog converter), power amplifier, attenuator, transmitting coil, and transmit/receive switch, etc. The receiver plays a role of amplifying and collecting magnetic resonance signals, and its performance directly determines a signal-to-noise ratio of a magnetic resonance spectroscopy.
A conventional receiver receives signals by cooperating with a plurality of array coils, and configures a same circuit to each channel, separately. This manner reduces the workload of the receiving system, while leaves a great redundancy on the signal processing ability of the receiving system. When the channels increase to a certain number, such simple repeatedly received circuit will make the whole receiving system extremely expensive and cumbersome.